G. Christodoulopoulos

Epidemiological survey of cestode-larva disease in Greek sheep flocks

The epidemiological status of hydatidosis, cysticercosis, and gid in sheep and the production practices of sheep farmers that increase the risk of exposure of sheep to infecting agents of these diseases were investigated in Thessaly, central Greece during 2002-2006. A total of 700 hoggets (sheep up to the age of 1 year) and 1500 adult sheep were examined randomly at an abattoir survey and the prevalences of hydatidosis and cysticercosis were found 39.32% and 29.41%, respectively. Hoggets had significantly lower prevalences of hydatidosis and cysticercosis compared to adult sheep (p<0.001). The distribution of parasitic cysts showed an overdispersion pattern mostly in the hogget population. The proportion of fertile hydatid cysts was significantly higher in hoggets compared to adult sheep (p<0.001). A cohort of 74 sheep flocks was observed during the same period in a prospective survey to assess the incidence of gid. A total of 57 sheep belonging to 15 flocks (20.27% of investigated flocks) developed clinical signs of gid at an annual rate of 11.40+/-4.77 (95% C.I.). In the infected flocks there were 3.80+/-0.92 (95% C.I.) gid cases per flock. The mean age of onset of clinical signs for all sheep was 11.86+/-1.33 months (95% C.I.) (range 5-22 months) while for hoggets was 8.48+/-0.73 (95% C.I.) (range 5-12 months) and for adult sheep 17.23+/-1.42 (95% C.I.) (range 13-22 months). A significant difference was observed in the prevalence of unilateral blindness between hoggets (31.42%) and adult sheep (4.54%) (p<0.05). The most common production practices identified in a questionnaire survey of sheep farmers that may increase the risk of exposure of sheep to hydatidosis, cysticercosis, and gid were the improper disposal of dead animals, the access of farm dogs to offal of slaughtered sheep, the carelessness of farmers to treat farm dogs with anthelmintics, and the grazing of flocks in fields where stray dogs have free access.

Foot lameness in dairy goats.

An outbreak of foot lameness in a dairy herd of 170 goats is described. The herd, that was kept mostly indoors, was attended between December 2006 and November 2007. During this period, 15% of the goats showed lameness with foot lesions and 24% of the goats showed lameness without foot lesions. The foot lesions consisted of cracks and erosions on the horn of the bulbs of the heel that in most cases extended along the internal side of the axial hoof wall. The clinical diagnosis was interdigital dermatitis. Annual milk production was lower in lame goats compared to those that were not lame (P<0.05). Furthermore, annual milk yield was significantly affected by the type of foot disease present and was significantly lower in cases with foot lesions than in the animals that were not lame (P<0.05) and also in the lame goats without foot lesions (P<0.05).

Influence of oestrus on the heat stability and other characteristics of milk from dairy goats.

We examined the heat stability, somatic cell count (SCC), pH, fat, protein and lactose content of milk from goats during the oestrous period, in order to investigate evidence of possible oestrus effects on milk physical and chemical properties. Goats free from mammary infections were ranked on average SCC from three tests so that they could be stratified randomly in pairs to synchronized oestrus or left as unsynchronized non-oestrus controls. The synchronisation consisted of insertion of an intravaginal progesterone-releasing device for 17 d, and introduction of the bucks the day of the device removal (D0). The repeated measurements analysis of variance model included the fixed effects of the experimental group (oestrus or control) and day and the corresponding interaction and also the random effect of doe. Reduced milk-heat stability, increased SCC, increased protein content and reduced pH were found in the milk samples of the oestrus group on D1, 2 and 3. The fat and lactose content of the milk was not affected by oestrus. These data indicate that the milk of goats during the mating period has reduced heat stability and, therefore, that dilution into bulk tanks should be recommended to avoid clotting when milk is intended for high thermal treatment.

The role of lactate dehydrogenase, alkaline phosphatase and aspartate aminotransferase in the diagnosis of subclinical intramammary infections in dairy sheep and goats

The objective was to investigate the changes occurring in the activities of the enzymes lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and aspartate aminotransferase (AST) in sheep and goat milk as a result of subclinical intramammary infections (IMI) and to evaluate the use of these enzymes for the diagnosis of subclinical IMI in dairy sheep and goats. A total of 206 samples of sheep milk and 162 samples of goat milk, obtained from equal udder halves, were used in the study. For each species they were divided into two groups: a no-infection group and a subclinical infection group. Activities of LDH, ALP and AST were significantly higher in the subclinical infection group than in the no-infection group (P<0.05) in both sheep (LDH: 350.42+/-11.25 v. 120.91+/-4.41; ALP: 2773.43+/-105.18 v. 2189+/-94.24; AST: 29.57+/-0.74 v. 17.32+/-0.46) and goats (LDH: 354.07+/-13.33 v. 103.79+/-3.75; ALP: 311.13+/-25.74 v. 137.24+/-19.62; AST: 27.59+/-6.42 v. 15.87+/-0.45). The activity of LDH was identified as indicator for subclinical IMI in both sheep and goats. The optimum cut-off values for LDH activity, offering the highest diagnostic sensitivity (DSn) and diagnostic specificity (DSp), determined by receiver operating characteristic (ROC) analysis, were at 197 U/l, 185 U/l and 197 U/l for sheep, goats and both species, respectively. DSn for sheep, goats and both species at these cut-off values was 92.8%, 98.2% and 94.0%, whereas DSp was 95.4%, 96.3% and 96.3%, respectively. It was concluded that the determination of LDH activity in milk serum is a sensitive and reliable method for the detection of subclinical IMI in dairy sheep and goats.

Alternatives to antibiotics for farm animals

Nowadays, there is an increasing concern for the public health about the consequences from the long and increased use of antibiotics in livestock production. The use of antibiotics in animal feed as growth promoters has been completely banned by the European Union since 2006, based on their possible negative effects on human and animal health. The removal of growth promoters has led to animal performance problems and a rise in the incidence of certain animal diseases. Thus, there is an urgent need to find alternatives to antibiotics, especially in EU. Due to the modern consumers’ concern about the potential development of antibiotic-resistant bacteria as well as at the same time the need to prevent economic losses of the farmers, alternatives to antibiotics has been developed to prevent the health problems and to improve the growth performance in farm animals. Owing to the full ban of antibiotic use in EU there is an urgent need to find alternatives to in-feed antibiotics. New strategies and commercial products must be developed to improve animal health and performance, based on their safety, efficacy and cost-effectiveness. The aim of this study is to summarize the beneficial effects of currently used alternatives to in-feed antibiotics, i.e. probiotics, prebiotics, organic acids, phytogenic compounds and zeolites on health and growth performance in farm animals (swine, poultry and ruminants).

Reproductive performance of sows was improved by administration of a sporing bacillary probiotic (Bacillus subtilis C-3102).

This field study assessed the efficacy of a probiotic based on viable spores of Bacillus subtilis C-3102 (Calsporin; Calpis Co. Ltd., Japan) on the health status and productivity of sows and their litters through 2 full, sequential reproductive cycles from service of the first cycle to weaning of the second cycle. Fifty-six sows were allocated to 2 experimental groups, an untreated control (T1) group and a probiotic-treated (T2) group that received the same basal feed as the T1 group plus the probiotic at an approximate allowance of 30 g/t of feed (3 × 10(5) cfu/g). The offspring of T1 and T2 sows were offered basal and T2 creep feed (3 × 10(5) cfu/g), respectively. Health and zootechnical parameters of sows and piglets were recorded. Feeding the probiotic to sows and piglets resulted in significant benefits, observed in both cycles: 1) improved sow body condition during pregnancy (P < 0.05), 2) increased sow feed consumption, 3) reduced sow weight loss during lactation (P < 0.05), 4) reduced sow weaning-estrus interval (P < 0.05), and 5) higher BW of piglets at weaning (P < 0.05). Additionally, a significant (P < 0.05) improvement in piglet birth weight and in the number of piglets weaned was observed in the second cycle of T2 sows, while a significant improvement of mean daily gain of piglets from birth to weaning was observed in the first cycle of T2 sows. Microbiological examination of fecal samples showed that probiotic treatment significantly reduced both Escherichia coli and Clostridium spp. in piglet feces, particularly during the second cycle. The data suggested that continuous feed supplementation with the probiotic is beneficial for both sows and piglets, since zootechnical benefits were observed in both cycles.

Selenium concentration in blood and hair of holstein dairy cows

Four-hundred Holstein cows in 40 dairy farms in north Greece were included in this study, and blood (n=400), black hair (n=400), white hair (n=40), and feed (n=40) samples were obtained. Although the feeding regime in these farms was similar, the selenium content of feeds was variable. The Se content of concentrate feeds was 0.104±0.086 mg/kg dry matter (DM), and of silage, it was 0.025±0.018 mg/kg. A significantly positive correlation was found between the Se concentration in black hair and the Se concentration in blood (r2=0.610, p<0.001), the Se concentration in white hair and the Se concentration in blood (r2=0.770, p<0.001), and the Se concentration in white hair and the Se concentration in black hair (r2=0.921, p<0.001). The Se concentration in white hair was significantly smaller than that in black hair (p<0.001).

Occurrence of non-cerebral coenurosis in sheep

This study reports seven rare cases of non-cerebral coenurosis in sheep. The sheep were slaughtered in abattoirs of Abu Dhabi (United Arab Emirates) but originated from India, Iran, Oman and Sudan. The prevalence of infection with non-cerebral coenurosis was 0.008%. The locations of the cysts were the triceps brachii muscle, the diaphragm, the infraspinatus muscle of the shoulder, the muscles of the thigh and the abdomen, and the ommentum. The Coenurus cysts were surrounded by a fibrous, semi-opaque membrane, cloudy white in colour. Altogether, 12 cysts were recovered and all contained a single bladderworm. Cysts had a volume of 7.3 ± 1.30 cm3 (ml), with 7.3 ± 4.0 clusters of scolices, and an average number of scolices 75.3 ± 24.4. These features in sheep were similar to those reported for non-cerebral Coenurus cysts in goats. No cysts were found in the brain or spinal cord of any of the infected sheep. No clinical evidence of non-cerebral coenurosis had been recorded during the antemortem veterinary inspection of the infected sheep.

Evaluation of a portable glucose meter for use in cattle and sheep.

BACKGROUND In farm animal practice, determination of blood glucose concentration under field conditions is often necessary. OBJECTIVE As there is no portable glucose meter device developed for use in farm animals, the analytical accuracy of a portable glucometer designed for people was evaluated for its use in cattle and sheep. METHODS Blood samples from 90 cattle and 101 sheep were used in the study. Glucose concentration was determined in whole blood immediately after blood collection from the jugular vein with the One Touch Vita portable glucometer and in serum with an enzymatic colorimetric method. The agreement between methods was assessed by Passing and Bablok regression analysis. The precision and the accuracy of the measurements were determined using the concordance correlation coefficient. RESULTS There was a strong linear relationship between the glucose values obtained using the portable glucometer and those obtained by the bench method in both cattle and sheep. Precision was 95% for cattle and 88% for sheep, whereas accuracy was 92% and 99%, respectively. The mean glucose values obtained using the portable glucometer were significantly lower by 8.3% in cattle and 3.2% in sheep than those determined by the bench method. CONCLUSION The One Touch Vita portable glucometer can be used in clinical practice to determine blood glucose concentrations in cattle and sheep, but reference intervals (RI) must be corrected to allow for negative bias. Based on these equations the RI for blood glucose in cattle and sheep using the portable glucometer were corrected to 1.84-4.17 and 2.41-4.35 mmol/L, respectively.

Effect of long-term dietary supplementation with clinoptilolite on performance and selected serum biochemical values in dairy goats

OBJECTIVE To determine the effect of dietary supplementation with clinoptilolite on health and production as well as serum concentrations of fat-soluble vitamins, macroelements and trace elements, and activities of hepatic enzymes in dairy goats. ANIMALS 72 Saanen-cross dairy goats. PROCEDURES Goats were randomly assigned to 1 of 2 groups. The clinoptilolite group (n = 36) received concentrate feed, of which 2.5% contained clinoptilolite; the control group (36) received unsupplemented feed. The experiment began 8 weeks before parturition and continued to the beginning of the next nonlactating period (280 days of lactation). At the day of parturition, kids were weighed. Milk yields were recorded at day 60 of lactation and thereafter at monthly intervals. Milk percentages of fat, protein, and lactose and somatic cell count (SCC) were evaluated at the same points. Blood samples were obtained at the beginning of the experiment, the day of parturition, and thereafter at monthly intervals to measure serum concentrations of fat-soluble vitamins, macroelements and trace elements, and activities of hepatic enzymes. RESULTS Birth weights of triplets and quadruplets were significantly higher in clinoptilolite-treated goats versus control goats. Milk fat percentage was significantly higher and SCC was significantly lower in clinoptilolite-treated goats, compared with respective values in control goats. However, no changes in serum concentrations of any variable were detected. CONCLUSIONS AND CLINICAL RELEVANCE In the context of this experiment, clinoptilolite supplementation of concentrate feed at 2.5% improved milk fat percentage in dairy goats, without adverse effects on the serum variables evaluated. Furthermore, the reduction of SCC achieved with clinoptilolite supplementation provided some evidence of improved milk hygiene.